The invention relates to a water-dispensing appliance, in particular for dispensing drinking water, comprising a water inlet which is adapted to be connected to a water-supply device, also comprising a dispensing device with a water outlet, via which water can be dispensed from the appliance, the dispensing device being connected to the water inlet via a main line which has a downstream portion and an upstream portion, and also comprising a water heater.
The invention also relates to a drinks-dispensing arrangement with a water-dispensing appliance.
Water-dispensing appliances of the type in question are usually connected to the public water-supply network, but may also be connected to some other water-supply means, for example a pump. They are often in the form of so-called water dispensers, which can dispense drinking water and are set up, for example, in public buildings, hotels, stores or hospitals, etc. As an alternative, water-dispensing appliances of the type in question may be designed as so-called under-counter or under-sink appliances which can dispense water via sink fittings. Common to all variants is the problem of dispensing water to a consumer in as germ-free a manner as possible. On the one hand, the bacterial content of the water which is to be dispensed is predetermined by the quality of the water provided by the water-supply device. In addition, there is a risk of contamination of water stored in the appliance.
In order to dispense sufficiently germ-free water, DE 35 12 880 C1 proposes a water-dispensing appliance of the type in question in which the water supplied from the water-supply device is heated to approximately 95° C. for at least 3 minutes by a water boiler incorporated in the main line before the water is dispensed from the appliance. The heating operation kills off bacteria contained in the water. In order to avoid contamination of the water in the main line when the water-dispensing appliance is inactive, a thermal sterilizing operation is provided in which that region of the main line which is disposed downstream of the water boiler is flushed with the hot water. The heat transferred from the hot water to the main line likewise sterilizes the latter. The hot water is then discarded, so that the sterilizing operation involves high energy and high water consumption. Moreover, the sterilizing operation covers only those portions of the main line which are located downstream of the water boiler.
It is an object of the present invention to provide a water-dispensing appliance of the type in question which can be used to carry out a thermal sterilizing operation with relatively low energy consumption.